The SN54/74LS90, SN54/74LS92 and SN54/74LS93 are high-speed 4-bit ripple type counters partitioned into two sections. Each counter has a divide- by-two section and either a divide-by-five (LS90), divide-by-six (LS92) or divide-by-eight (LS93) section which are triggered by a HIGH-to-LOW transition on the clock inputs. Each section can be used separately or tied together Q to CP) to form BCD, bi-quinary, modulo-12, or modulo-16 counters. All of the counters have a 2-input gated Master Reset (Clear), and the LS90 also has a 2-input gated Master Set (Preset 9).


* Low Power Consumption . . . Typically 45 mW
* High Count Rates . . . Typically 42 MHz
* Choice of Counting Modes . . . BCD, Bi-Quinary, Divide-by-Twelve, Binary
* Input Clamp Diodes Limit High Speed Termination Effects

SN54LS90 SN74LS90 SN54LS92 SN74LS92 SN54LS93 SN74LS93

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